208731268805 has 6 divisors (see below), whose sum is σ = 250478748486. Its totient is φ = 166984197768.

The previous prime is 208731268783. The next prime is 208731268813. The reversal of 208731268805 is 508862137802.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 166985015044 + 41746253761 = 408638^2 + 204319^2 .

It is not a de Polignac number, because 208731268805 - 2⁶ = 208731268741 is a prime.

It is a super-2 number, since 2×208731268805² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 919436 + ... + 1123754.

It is an arithmetic number, because the mean of its divisors is an integer number (41746458081).

Almost surely, 2^208731268805 is an apocalyptic number.

It is an amenable number.

208731268805 is a deficient number, since it is larger than the sum of its proper divisors (41747479681).

208731268805 is an frugal number, since it uses more digits than its factorization.

208731268805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408643 (or 204324 counting only the distinct ones).

The product of its (nonzero) digits is 1290240, while the sum is 50.

The spelling of 208731268805 in words is "two hundred eight billion, seven hundred thirty-one million, two hundred sixty-eight thousand, eight hundred five".